Concrete road surfacing



Sept. 2, 1969 ADOLPHE-LEON NAGET CONCRETE ROAD SURFACING 6 Sheets-Sheet 2 Filed Jan. 16, 1967 FIG. 77

5 JGR. \QFZocns Mae fip 1969 ADOLPHELEON NAGET 3,464,329

CONCRETE ROAD SURFACING Filed Jan. 16, 1967 6 Sheets-Sheet 5 FIG. 10 39 l I l l I l I l l l I I l M and,

KM. mocks p 1969 ADOLPHE-LEON NAGET 3,

CONCRETE ROAD SURFACING 6 Sheets-Sheet 4 Filed Jan. 16, 1967 FIG. 1/

ADOLPHE-LEON NAGET 3,464,329

' CONCRETE ROAD SURFACING Sept. 2 1969 6 Sheets-Sheet 5 Filed Jan. 16, 1967 I illllll p 1969 ADOLPHE-LEON NAGET 3,464,329

CONCRETE ROAD SURFACING 6 Sheets-Sheet 6 Filed Jan. 16, 1967 United States Patent Int. Cl. EOlc 19/20, 19/41 US. Cl. 94--44 3 Claims ABSTRACT OF THE DISCLOSURE An equipment of at least two machines on rails for the preparation and continuous laying of a concrete road surface, the rolling tracks of the machine being finally incorporated in the road surface, and the stony bed being deposited dry between the rolling tracks without passing through a concrete mixer, a first machine effecting the homogeneous mixing of the stony bed and the binder, and a second machine effecting the vibration and ramming of the concrete.

The present invention concerns a concrete surfacing for roads, and relates more particularly to a continuous process for laying road surfaces of stones and mortar, its mixing and ramming, and also the equipment of machines provided for the application of the process and to lay the road surface without interruption in the succession of operations.

Machines for mixing concrete and machines intended for consolidating concrete in position are already known. Rolling tracks on which the machines run as they operate on road-works are also known.

However, these machines are intended to carry out their functions separately and in a manner independent of each other, and the result is that the preparation of road surfaces of concrete has involved up to the present time, operations which are carried out under bad conditions, the cost of intermediate labour and auxiliary work such as the installation of rolling track cofferings which do not directly contribute to the achievement of the chosen object. These result in substantial and irrecoverable expenses, Wasted hours of work and irrational utilization of the equipment.

The present invention has mainly for its object to provide a continuous process for laying a road surface, in which the area to be covered is limited by edges which serve as a running track for the machines and which are incorporated in the useful width of the span covered, in which the rolled stones and pebbles are spread out evenly in the dry state between the said edges, only the binder or sand and cement mortar being passed through the concrete mixer, the laying of this binder on the bed of dry stones being immediately followed by the passage of a first mixing machine and a second ramming machine, the surface applied by the machines of the equipment according to the invention being thus capable of moving forward with a thickness of road concrete of 0.22 rn. at a rate of 500 linear metres per day of working, over a width of track of 7.50 m.

The invention has also for its object to provide:

An edging of concrete on which is provided the housing of a removable stirrup on which sleeper-screws hold the travelling rail of the machines of the equipment which apply the surfacing, on which edge is also provided in combination a hole made for an anchoring rod, this anchoring rod firmly fixing the edge to the surfacing when the latter has set;

A toothed cylinder carried by a mixing machine which passes above the span on the said rails and the speed of which is synchronized with the forward movement speed of the machine which ensures a uniform mixture from the bottom to the top of the bed of stones and the binder, and a divergent-convergent distribution of the surfacing materials between the edges;

A swan-neck tooth with special twin mounting fixed on the said cylinder;

A four by four assembly of the said teeth which ensures the mixing in sections of the materials spread uniformly over the span;

A ramming device carried by a compacting machine which comprises a jack for lifting a beam acting on a ramming shoe in relation with the movement of the wheels so as to ensure a cycle of movement during whichthe forward movement and the compacting action follow each other alternately, the duration of the compacting in each cycle and the degree of overlap of two successive positions of the shoe being adjustable at will.

A method in accordance with the invention thus comprises the following steps:

To prepare the extreme edges of the span to be surfaced, these edges having the final height of the surface and being included in the overall width of the final road;

To place on these edges stirrups and rolling rails of the machines of the equipment according to the invention;

To subject the mixture thus spread to the action of selfpropelled mechanical means, ensuring in situ and successively:

(a) A volumetric dosing of the above-mentioned materials;

(b) A mixing action, a stirring action and a divergent distribution with respect to the central line of the span of materials previously measured out;

(o) A fresh mixing action, another stirring action and a convergent distribution of the said materials with respect to the said central line of the span; and

(d) A vibrated compression of the concrete thus produced, the compression being immediately preceded by the placing in position of the anchorage rods.

In accordance with other characteristic features of the invention:

The volumetric dosing of the binder with respect to that of the bed of stones is ensured by means of a rule locked at the desired height above the reference level and moving transversely to the central line of the span or by an equivalent device, for example a blade drum or an Archimedean screw;

The mixing, the stirring and the divergent distribution of the measured materials are ensured by means of two transverse devices arranged symmetrically with respect to the central line of the span and each constituted by a series of teeth fixed on a common driving shaft so as to obtain a kind of Archimedean screw with teeth, the two screws thus formed being of opposite pitch and moving horizontally and at right angles to the central line of the span;

The complementary mixing and stirring operations and also the convergent distribution of the previously measured, mixed, stirred and divergently distributed materials are ensured by means of two Archimedean screws of oppositely directed pitches with helicoidal blades keyed on a common driving shaft and moving horizontally and at right angles to the central line of the span;

The compression of the concrete is effected 'by means of a transverse shoe fitted with vibrators, the said shoe moving step-by-step at right angles to the central line of the span;

In a particularly advantageous manner, there are combined on the one hand on a first self-propelled machine the means for carrying out the volumetric dosing of the constituent elements of the surface to be produced, to-

gether with the means for effecting the mixing, the stirring and the divergent distribution of the said materials; on the other hand, on a second machine, the means for carrying out the mixing, the stirring and the complementary convergent distribution of the materials together with the means for ensuring the compression of the concrete produced; and when so required, on a third machine, the means for carrying out the final levelling.

Other characteristic features and advantages of the invention will be brought out in the description which follows below, reference being made to the accompanying drawings and illustrating purely by way of indication and not in any limitative sense, one form of embodiment of the invention.

In the drawings:

FIG. 1 is a diagrammatic view of the succession of operations in the laying-down of a road surfacing over a. span according to the invention;

FIGS. 2 to 5 are transverse sections of the surfacing obtained during the course of the different phases of the work, taken respectively along the lines II-II, III-III, IV-IV, and V-V of FIG. 1;

FIGS. 6 and 7 are partial longitudinal sections of the surfacing to a larger scale, respectively before and after mixing in situ, taken along the lines VIVI of FIG. 2 and VIIVII of FIG. 3;

FIG. 8 is a perspective view of the toothed cylinder of the mixing machine A which distributes the bed of stones from the state shown in FIG. 6 to that shown in FIG. 7;

FIG. 9 is a view to the larger scale in side elevation of two swan-neck teeth of the mixing machine shown in FIG. 8;

FIGS. 10, 11 and 12 are details of construction of a device for securing the teeth of FIG. 9;

FIG. 13 is a view in elevation of a machine B for compacting the surfacing prepared by the mixing machine of FIG. 8;

FIG. 14 is a perspective view of a machine similar to that shown in FIG. 13;

FIG. 15 is a side view of the coupling device between the wheels and the ramming shoe of the machine of FIG. 13;

FIG. 16 is a detail view of the operation of the shoe of the machine shown in FIG. 13;

FIG. 17 reproduces diagrammatically a photograph of the section of mixed stone mortar obtained according to the invention.

There is shown in FIG. 1 a sketch of a span to be surfaced having its axis at X -X, the surfacing being laid in a continuous manner in the direction of the arrow f On edgings or kerbs rails 1 and 2 guide the forward movement of two machines according to the invention, indicated diagrammatically as units by A and B.

The rails 1 and 2 are separated from each other by a distance 1 corresponding substantially with that of the strip of road surfacing in concrete to be produced and which will be obtained at 80.

The width of this strip is very slightly larger than the distance I.

A vibrating levelling rod shown diagrammatically at C and, when so required, a levelling roller, preferably follow the machine B in order to complete the surface of the coating R laid by the machines A and B.

More particularly, the process comprises essentially the following steps:

(1) Over the width 1 of the span to be surfaced, in the zone Z located upstream of the machine A, the materials necessary for the production of the surfacing are spread out evenly, namely a bottom bed of dry stones or rolled pebbles 3 (see FIG. 6) over which is spread the binder 4 constituted by a mortar of sand and cement.

(2) The mixture thus distributed is subjected to the mechanical and automatic action of the machine A, which has the functions:

(a) of ensuring the volumetric dosing of the abovementioned materials by means of a levelling bar 5 arranged transversely to the machine and fixed at the desired height above the level of the rails 1 and 2, on which run the carrier and driving wheels 6 of the machine A (or of an equivalent device, for example a levelling drum with blades) in order to leave in its wake the height of binder 4 which is exactly necessary and suflicient to provide the complete coating of the constituent elements of the bed of stones 3;

(b) of ensuring mechanically the mixing, stirring and divergent distribution with respect to the central line X X of the constituent materials of the surfacing, previously dosed by the levelling bar 5. This is very simply obtained by means of two symmetrical mixerdistributor devices 7 and 8.

Each of these devices is constituted by a series of mixing teeth 9 which are keyed on a common transverse driving shaft 10 in such manner that they are helicoidally distributed around the said shaft 10 and form as a whole a kind of double Archimedean screw with teeth, in which it is important to note that the two screws 7 and 8 thus formed are of reversed direction of pitch.

In this way, the constituent materials of the zone Z are mixed, stirred and distributed in a divergent manner in the direction of the arrows f and f in order to form the surfacing of the zone Z which has the structure shown in FIG. 7 and the section of incurved form shown diagrammatically in FIG. 5.

It will of course be understood that the machine A is provided with a motor 11 which, through the intermediary of appropriate mechanical couplings, ensures both the forward movement of the machine and the synchronized rotation of the shaft 10, while the said shaft 10 is adjustable in height by means of height adjusting wheel 99. The number and the distance apart of the teeth 9 which constitute the devices 7 and 8, are determined as a function of the nature and the size of the materials utilized, and their arrangement will be described in more detail in the description which follows.

(3) The surfacing thus obtained in the zone Z is then subjected to the mechanical and automatic action of the machine B which has the functions:

(a) of mechanically completing the mixing and stirring of the materials treated by the machine A while at the same time ensuring a convergent distribution of the said materials with respect to the central line X -X.

As in the case of the machine A, this is obtained by means of two symmetrical distributor devices 12 and 13, each of which is constituted by a helicoidal blade mounted on a common transverse driving shaft 14, it 'being noted that the two sloping-face Archimedean screws thus formed are of opposite pitch and are respectively in opposite directions to the pitches of the devices in their alignment 8 and 7 of the machine A.

Thus, the constituent materials in the zone 2-,. are distributed in a convergent manner in the direction of the reversed arrows f, and f so as to constitute the surface covering of the zone Z which has the general texture shown in FIG. 7, but in this case the section is that shown in FIG. 4, that is to say it has a slight central additional thickness 15 of width 6.

It is important to note that this central over-thickness constitutes a visual means of checking that the quantities of materials employed are measured correctly so that they can be modified in consequence if necessary. In other words, there is obtained in a particularly simple and etfective manner a means of checking the adjustment of quantities of materials to be used, in order to obtain the best results;

(b) of effecting the ramming of the concrete thus produced by means of a transverse shoe 16 provided in a manner known per se with an appropriate number of standard commercial vibrators, for example three. The surface coating 80 is thus completed, it being understood there may be advantageously added to the machine B a vibrating finishing rod C in order to obtain the final surfacing of the zone 2,, the cross-section of which is shown in FIG. 5.

The machine B is further provided with a motor 43 which permits, through the intermediary of mechanical couplings and appropriate driving devices which will be referred to in more detail later, of ensuring both the forward movement of the machine and the rotation of the driving shaft 14 of the mixer-stirrer devices 12 and 13, and the movement of raising and lowering the ramming shoe 16.

It will of course be understood that the various movements are synchronized with each other and that the forward movement of the machine B on the rails 1 and 2 takes place step by step of about 15 centimetres per step, with a stop at each step corresponding to the time necessary for the pressing action of the shoe 16 on the concrete.

There will now be described an installation which for example permits the laying of a surfacing of concrete according to the invention, of 0.22 m. in thickness, at the rate of 500 linear metres per day of working over a width of road of 7.50 m.

The area or strip of road to be surfaced is bordered by two edging strips, the height of which is for example equal to 0.22 m. and the maximum distance 1 between these edges is equal to 7.50 m. On each edging strip there have been provided holes for the subsequent reception of anchorage rods.

It is between the edging strips that the materials necessary for the road are evenly spread out, as previously explained.

At intervals along the edges, there are provided metal stirrups on which holding-down bolts hold the rail 1. A rail 2 is fixed on the opposite parallel edge in a similar manner.

Along the rails 1 and 2 passes first the machine A which converts the mixture of materials necessary for the road to the condition shown by the profile of FIG. 7 from the section of the profile shown in FIG. 6.

The machine B then comes into action according to the operation shown in FIG. 13. The wheels 6' rest on the rail 1, and in front of the machine the Archimedean screw 12 and 13 levels the concrete and brings the additional thickness towards the centre of the area to be covered. A hand-wheel 23 permits the lifting at will of the arms 24 which carry the shaft 14 of the screw 12, 13 of opposite pitches.

The screw 12, 13 is driven by a chain 25 passing over an idler pinion 26 which is tensioned by the spring 27.

The chain 25 passes over a reduction gear 28 driven by the auxiliary engine 29.

At the rear of the engine 29, there is seen a vibrator device 30 which acts on a vibrating shoe 16 shown on the drawing in the top position corresponding to a period of displacement of the machine. The shoe 16 is vibrated by means of three vibrator devices and is fixed to a girder articulated at 31, and has the purpose of ramming down the concrete in an absolutely straight manner to the predetermined height desired. It also effects a vibrating action vertically by alternate cycles of forward movement of the machine of more than one metre per minute.

Finally, at the extremity of the machine B opposite to the Archimedean screw 12, 13 is located a vibrating bar C which ensures the finishing of the coating surface. The bar can also be mounted on a separate following machine provided with a roller for finish-levelling.

Certain details of the operation of the machines A and B will now be examined, with more particular reference to FIGS. 8 to 16.

It can be seen that the shaft of the machine A carries swan-neck teeth 9. According to the invention,

these teeth are arranged in twin pairs 9a, 9d and 9b, 9c. The tooth 9a is displaced in front of the tooth 9b with respect to the movement of rotation of the teeth represented by the arrow f and the two pairs of teeth 90, 9d, and 9b, 9c constitute an assembly of four teeth, in which the teeth 9a and 9d pass into the bed of materials before the teeth 9b and 9c, the four teeth forming a kind of openwork shovel or spoon.

The assembly 32 of the four teeth located furthest to the left of FIG. 8 (looking on the front of FIG.8) is immediately followed by a similar assembly 33 which is in advance by about 20 of are on the average with respect to the assembly 32 in the direction of movement of rotation indicated by the arrow i which drives the cylinder 10. This is also the case for the assemblies following up to the assembly 34 shown at the top of FIG. 8, which is located in the centre of the cylinder 10 and In consequence in the axis X X of the span of materials spread out evenly over the roadway.

The other side of the mixing machine (the right hand side looking on FIG. 8) has a symmetrical arrangement of the teeth 9.

The mounting of the teeth and 9d on the shaft 10 is more clearly shown in FIG. 9. There is seen a halfsleeve 35 fixed to a special half-collar 36, in which two housings 37 and 38 are provided respectively to rece1ve the teeth 9d and 90.

It can be seen that all the teeth 9 are identical, easily removed, but once placed in position on the mounting device they necessarily form between each other an angle at defined by the construction of the housings 37 and 38.

A cap 39, a back-plate 40, and a locking member 41 complete the mounting of the half-sleeves 35 and 36 around the shaft 10, on which they are locked in position by force by means of nuts and bolts 42.

It W111 be noted that two symmetrical types of the speclal half-collar 36 and of the cap 39, a left-hand type and a right-hand type, in order to form an assembly 32 of four swan-neck teeth according to the invention.

With regard to the operation of the shoe 16 of the mach ne B, reference will be made to FIGS. 14 and 15.

ack 43 can lift, or permit to fall to its bottom position, the ramming unit, weighing for example 2.5 tons, by means of the lifting arms 44. The lifting arms are coupled to the shafts 45 and 46. The shoe beam 16 can be held locked in the top safety position by means of a key which keeps the holes 47 and 48 opposite each other during the movements of the machine, outside the working periods.

The jack 43, coupled at 49 to the frame of the machine, carries a piston, the arm 50 of which lifts under the action of a pushbutton within reach of the driver of the machine, when this latter gives an order to move forward. The pivot of the articulation 51 simultaneously drives the arm 52 which controls, through the intermediary of the plates 53, the rotation of the wheel 6 on the rail 1, and the shafts 45 and 46 which are coupled to the lifting arms 44 and 44' respectively.

In the position of the machine shown in FIG. 15, the jack 43 moves upwards in the direction of the arrow f moving lifting arm 44 in an upwardly rotating direction of arrow i and reaches the end-of-ramming position at which the shoe no longer comes in contact with the ground. Continuing its travel, the pivot 51 reaches 54 and at that moment, through the intermediary of an elongated slot 55 in which the shaft 56 is engaged, the arm 52 drives the cross-arm 57 round the bracket 58. The crank 59 drives the driving wheel 6 by means of two series of teeth, for example two series of six teeth 60 on two ratchet plates 53 mounted on each side of the wheel 60, on which are engaged the two ratchets 61 fixed on the wheel 6'. The Wheel 6' can be freed from the propulsion system by locking the ratchets 61 in the withdrawn position.

When the pivot 51 is at 62, the beam shoe is located in its maximum lifted position. It is only necessary to release the pressure in the cylinder 43 for the beam to move down into the ramming position, the two ratchet plates 53 then moving back so as to be ready to drive the wheel 60 again during the course of the next following cycle.

The forward movement must take place with a certain delay after the order of lifting of the beam shoe 16, in order that this beam 16 does not push back the materials 63 which swell out after the mixing in front of the rammed zone 64 (see FIG. 16). It is for this purpose that the play inside the elongated slot 55 is provided at the extremity of the arm 52.

In one example of construction, the width of the beam shoe is 160 mm. The overlap provided between two positions is 20 mm. and the ramming period is 8 seconds. Depending on the rapidity of reaction of the machine, there may be obtained 7 and 8 cycles per minute, which results in 7 times 0.14 m.=0.98 m. to 8 times 0.14 m.=1.12 m. of average forward movement per minute.

Finally, as shown in FIG. 17, there is obtained a block 65 of road surfacing, in which the materials have been mixed according to the invention. This block was separated after the mortar had set, by drilling holes 66, and was then sawn across at 67. The sawn block 67 shown resting on the perfectly fiat surface 80 of the road surface, shows the distribution of the pebbles 3 coated in a matrix of binder distributed in a uniform System throughout the entire thickness of the surfacing. It will be recalled that these pebbles were evenly spread out in successive beds in the dry state on the roadway and were then mixed in situ with the mortar by means of the propelled mixer according to the invention.

This excellent result was obtained by means of a machine moving forward with a continuous motion by 1.05 111. per hour, the speed of rotation of the shaft being 26 r.p.m.

It can be seen that the whole of the method and the means described above makes it possible:

To provide a road surfacing which is perfectly calibrated, rammed and finished;

To avoid passing into the concrete mixer two-thirds of the filling materials, the latter, dry gravel and road pebbles, being placed in bulk on the road before placing in position the bed of wet mortar binder;

To incorporate in the useful width of the road the supporting edges of cement concrete which, in the methods of the prior art, represent an expense additional to that of the layer of concrete proper, this nonrecoverable expense being avoided by the present invention;

To operate on continuous working by cycles, thus avoiding any loss of time or any bad utilization of the equipment.

It will of course be understood that the present invention has been described above purely by way of explanation and not in any limitative sense, .and that any modification of detail may be made thereto in conformity with its spirit without thereby departing from its scope.

I claim:

1. Machine equipment for preparing and laying down concrete road surfaces over an area comprising:

track supporting the machine equipment;

a first wheeled machine having means for distributing a layer of mortar over a stony bed previously spread out evenly between said tracks, a levelling and strikeotf bar, a first cylinder with mixing teeth, a driving motor for the forward movement of the wheels of said first machine actuating the drive of said toothed cylinder in synchronism with that of said wheels; and

a second wheeled machine having a second cylinder with two Archimedean screws of opposite pitch convergent towards the axis of the area to be covered, a driving motor of said second machine connected to a shoe by linkage means to raise and drop said shoe, and operatively coupled to a wheel through the intermediary of a coupling rod system to operate said wheel only when said shoe is lifted to its inoperative position, and permitting the shoe to fall to its operative position at the moment when the action on said wheel is interrupted whereby dropping of said shoe and rotation of said wheel is intermittent;

said toothed cylinder having swan-neck teeth which are curved back in the direction of rotation of said cylinder in a counterclockwise direction so as to engage into the bottom of said bed of materials, said teeth being divided into groups in the form of a scoop.

2. Machine equipment as claimed in claim 1, in which said group of teeth of scoop shape comprises at least two outer teeth in advance on the two inner teeth with respect to the direction of rotation of said cylinder, the groups being staggered with respect to each other by a certain angle symmetrically on each side of the axis of the area to be covered, forming two Archimedean screws of opposite pitches.

3. Machine equipment as claimed in claim 2, in which said teeth are identical and are mounted in pairs between two half-sleeves in which housings are provided in such manner that the general direction of each tooth forms a certain angle a with the direction of the neighbouring tooth, the correct assembly of said cylinder requiring two different types of sleeves symmetrically disposed so as to obtain with one pair of sleeves said group of scoop shape.

References Cited UNITED STATES PATENTS 2,035,627 3/1936 West 9446 2,041,350 5/1936 Johnson.

2,098,895 11/ 1937 Velten 9449 2,116,816 5/ 1938 Winkler 9449 2,214,702 9/ 1940 Seaman.

2,346,379 4/ 1944 Jackson 9444 XR 2,368,331 l/1945 Seaman 9440 3,359,875 12/1967 Reider 94-46 XR JACOB L. NACKENOFF, Primary Examiner U.S. Cl. X.R. 

